Electric remote control apparatus



y 1932- G. DOUGLASS ET AL 1,863,002

ELECTRIC REMOTE CONTROL APPARATUS Filed Oct. 22, 1928 7 Sheets-Sheet lJuly 19, 1932. G. DQUGLASS ET AL ELECTRIC REMOTE CONTROL APPARATUS FiledOct. 22, 1928 7 Sheets-Sheet 2 July 19, 1932. G. DOUGLASS ET AL1,868,002

ELECTRIC REMOTE CONTROL APPARATUS Filed 000. 2.2, 1928 '(Sheets-Sheet 5July 19, 1932. G. DOUGLASS ET AL ,0 2

ELECTRIC REMOTE CONTRQL APPARATUS Filed Oct. 22, 1928 7 Sheets-Sheet 4July 19, 1932. G. DOUGLASS E1; AL 1,868,002

ELECTRIC REMOTE CONTROL APPARATUS Filed Oct. 22, 1928 '7 Sheets-Sheet 5f 40 #6 was 40a F n H 7 July 19, 1932. G. DOUGLASS ET AL 1,863,002

ELECTRIC REMOTE CONTROL APPARATUS Filed Oct. 22, 1928 7 Sheets-Sheet 6Fly/9'? 2c Z 25 ZF 26' 2% 272x222,"

O O O O O o O O O 1 M 43 4642 4:41 41:44 a o o 0 o o o o o, o

y 19, 1932- G. DOUGLASS ET AL 1,363,002

ELECTRIC REMOTE CONTROL APPARATUS Filed 001,. 22, 1928 7 Sheets-Sheet 7az a2 82 8f Patented July 19, 1932 UNITED STATES PATENT crimes GORDONDOUGLASS, F KENSINGTON, LONDON, AND STANLEY ROBERT .WRIG-HT, OF

BEDFORD, ENGLAND I ELECTRIC REMOTE CONTROL APPARATUS 7 Application filedOctober 22, 1928, Serial No. 314,258, and in Great Britain October 24;1927.

This invention relates to, and has for its object the provision ofimprovements in remote control" apparatus.

The invention consists broadly of two units driven by means of a commonmotor, one of said units being adapted to control said motor so that thesame is automatically stopped after said unit has been driven a givenamount and the other unit being adapted to 39 control the controlleddevice or devices, preselecting means being provided for stopping saidlatter unit after being driven a predetermined amount which amount mustbe completed before the motor is stopped by the former unit, said latterunit being driven through the medium of a friction clutch so that themotor and the former unit may continue running after said latter unit isstopped. In order that the invention may be the more clearly understoodtwo signalling systems in accordance therewith for displaying, atvarious rooms of a hotel, under control from a central operatingstation, the room number of any visitor who may be wanted will now bedescribed with reference to the accompanying drawings. In each of thesesystems a display set is located in the vicinity of each room,comprising four rotors each of which carries numerals at spacedintervals around the periphery thereof and which are screened so thatonly one of each is visible at a time the four visible numerals being ina legible row. Thus by selecting the angular positions of the severalrotors any number of less than ten thousand can be displayed in the saidroom.

It is not necessary in the present specification to describe the displaysets in detail. It is sufficient to say that each rotor has threeenergizing circuits and is adapted to be rotated in a step by stepmanner in response to the sequential energization of these circuits incyclic order. In the case of the present systems each rotor hastwenty-four steps of rotation per complete revolution and the numeralschange in response to each two steps. In U. S. Patent No. 1,098,617 maybe seen as example of a rotor adapted to be rotated in a step by stepmanner in response to the sequential energization of a number of cir:

cuits.

In the drawings Figure l is a side view of one offour controllersemployed in one of said systems for respectively controlling the fourrotors of each set.

Figure 2 is an end, view of a said controller.

Figure 3 is a side view to an enlarged scale illustrating the operationof certain of the parts of Figure 2.

Figure 4 is an end view of another portion of said controller. 1

' Figures 5 and 6 are side views to an. enlarged scale illustrating theoperation of certain of the parts of Figure 4.

Figure 7 is an outside view in front elevaportion of tion of the wholecontrol apparatus employed in the other of said systems.

Figure 7 a is a similar View in side elevation of the same. I

Figure 8 is a perspective View of a part of one of the transmissionunits thereof. 1

Figure 9 is a sectional elevation of one of the parts shown in Figure 8.I Figure 10 is a perspective view of a contact panel incorporated ineach transmission unit. Figure 11 isan end elevation of certain of theparts associated with each transmission unit.

Figure 12 is an end elevation of other parts associated with saidtransmission unit.

Figure 13 shows one portion of adiagram of connections of the wholesystem;

Figure 13a shows the other half of the same. Figure 14 illustrates amechanical interlock between two push button switches included in Figure13.

Describing first the controller illustrated in Figures 1 to- 6 the samecomprises ten selector members 1 bearing respectively the nu merals from0 to 9 and a control member '2, the arrangement being such that uponmove ment of a given selector member to the selecting positions andsubsequent actuation of said control member the three circuits of thecor:

responding rotor (or rotors if more thanv one display set is employed)will be sequentially energized until such time as said rotor isdisplaying the numeral carried by the said selector member. Thesequential circuit energization will then stop and subsequently awarning note will be sounded and the display number will be illuminated.

Thus said controller comprises one controlling unit 0 and one dialingunit (Z. The dialing unit comprises three discs 4, 5 and 6 rigidlymounted on a common shaft 7, the saiddiscs being adapted upon rotationrespectively to make and break the three rotor controlling circuits. Tothis end each disc bears a number of cam projections 8 on its peripheryand has an associated normally open switch 9 which said cam, projectionsare adapted to engage and thereby close sequentially. The three switches9 are respectively connected in the three rotor control circuits. Theperipheral cam projections 8 of each. disc are staggered with respect tothose of the other discs as shown so that the said rotor controlcircuits will be energized sequentially as the discs rotate and therotor will. move one step each time a peripheral cam projection 8engages with a-switch 9. The total number of cam projections is selectedso that one complete revolution of the discs is accompanied by acomplete revolution of the rotor and it will thus be seen that theangular position of the discs will. always exactly correspond with thatof the rotor.

The shaft 7 is adapted to be driven by means of'an electric motorthrough the medium of a somewhat light friction clutch 11. The aforesaidselector members 1 take the form of rods arranged parallel to, and atspaced intervals around said shaft 7. The rods are longitudinallyreciprocable each to and from a non selecting position and a selectingposition in which it obstructs the path of a stop projection 12 mountedin rigid relationship with said discs, and the location of the rods issuch that when the one bearing a given numeral is moved to its selectingposition the said stop 12 will engage with it and effect stoppage of thediscs at such a position that the same given numeral. will be displayedby the rotor. It will be appreciated that by virtue of the frictionclutch 11 the motor is permitted to continue running after the dialingunit has been stopped in this way.

The rods 1 pass through holes in a plate 13 which is oscil'latableagainst and with a spring 13a and said rods having projections 14 whichinterlock with said holes in such a way that upon any rod being pressedto the opera tive position any other rod which be at the operativeposition flies back to the inoperative position (under the influence ofits controlling spring illustrated.) said former rod being retained atits operative position until pressure of another rod to its operativeposition releases it.

The controlling unit 0 comprises a single disc 15 rigidly mounted on ashaft 25 and adapted to be rotated through the medium' of av frictionclutch 16 by the same electric motor which drives said dialing unit.This controlling unit is adapted to control a switch 17 in the powercircuit of the motor in such a way that at only one position of the disc15 said power circuit is open and the motor is at rest and at all otherpositions of said disc 15 said power circuit is closed and said motor isin operation The control member 2 hereinbefore referred to consists of alongi tudinal reciprocable rod actuating a radial arm 20 hearing a pawl21 and spring 22 said rod being biassed to one end of its stroke bymeans of a spring 23. The radial arm is so correlatedwith a ratchetwheel 24 mounted on said shaft 25 that depressions of said rod inopposition to its spring 23; effects rotation of said disc 15 bypermission of said friction clutch 16) through a few degrees; The speedratio of said disc 15 relative to said discs 4. 5 and 6 is such that theformer rotates a little more slowly than the'latter.

The disc 15' being at the said position at which the power circuit ofthe motor is open and the display of a given numeral by the rotor beingrequired, the selecting member 1 bearing the said numeral" is moved tothe se lecting position and the control member 221s depressed. Thislatter operation rotates the disc 15 a few degrees and tie motor circuitis thereby established. The motor commencesto run and both the discs'lto 6 and the disc 15 are rotated the latter in the same direction inwhich its movement was commenced. by the operation of the control member2.

lVhcn the stop 12 engages the said selecting member 1. the discs 4 to 6will be stopped and consequently the rotor will be also stopped with therequired number displayed. Owing to the speed ratio of the two unitsabove referredto this stoppage ofthe discs 4 to 6 is bound to occurbefore the disc 15has made a complete revolution. When said "contro lingunit 15 has made a complete revolution the motor power circuit will beonce more opened and the motor will stop.

In order that the, warning signal and illumination aforedescribed shallbe effected said controlling unit carries two contacts 26, 27 whichrotate with the disc 15 adapted to en gage with respective fixedcontacts 28, 29. One of these engagements (27, 28) is adapted to beeffected whilesaid disc 15'is at its said motor stopping position and isadapted to e tablish circuit for illuminating the displayed number assoon as, and so long as, the motor is at rest. The other'eugagement (26,29) is adapted to be as cted temporarily ust before the disc 15 arrivesat its said position. This establishes a circuit for sounding a buzzeror the like. Additional contacts can be added for operating otherauxiliary circuits if desired. 1;;

Lamps of different colours visible to the operator may be adapted tolight according as whether the apparatus is in operation or at rest.

It will be clear that for a set of four rotors, four dialing units willbe required, one. associated with each rotor but only one controllingunit and motor will be required. In this case one selector member 1 ofeach dialing unit will be set and the control member 2 subsequentlydepressed.

Describing certain constructional details, dialing unit or units and thecontrolling unit are all worm driven from the driving shaft of themotor.

The pawl 21 carried by the arm 20 is adapted to be biassed intoengagement with the ratchet wheel by means of a flat spring 31 carriedby the disc 15. hen said flat spring is moved away from said pawl thelatter is biassed away from the ratchet wheel by means of av feeble coilspring 22. Thus said pawl 21 is only operative when the controlling unitis at its motor stopping position and any interference with the controlmember 2 when the motor is running is ineffective.

The control by the disc 15 of the said switch 17 in the power circuit ofthe motor is effected by virtue of the co-operation of a recess 18 cutin the periphery of said disc 15 and an operating arm 32 associated withsaid switch. WV hen the disc 15 is at the given position said arm fallsinto said recess and the switch is at the open position. When the discis at any other position said arm rests against the periphery of saiddisc and the switch 17 is at the closed position.

Describing now the system illustrated in Figures 7-13 the controllingapparatus at said central station comprises a common electric motor 66and a number of transmission units T corresponding to the number of thedisplay sets D. The transmission units are all incorporated into asingle structure and are arranged one above the other as in dicated inFigure 7.

Each transmission unit T comprises a horizontal shaft 33, anelectromagnetic clutch 67 through the medium of which and an endlesschain a said shaft is adapted to be driven by said common motor 66, andfour selecting devicesone for each of the four rotors (Z of the displayset controlled by said transmission unit. The electromagnetic clutch 67has one element 67a rigid on the shaft 33 and the other 676 runningloose on said shaft. The latter element 677) is hollow and contains themagnet whereby said element is drawn into driving engagement with theelement 670,.

This magnet is energized through stationary wiping contacts 670 and sliprings 67d mounted on, and insulated from the element 677). The toothedwheel 67 e on which the chain a drives is of course rigid with theelement 67 b.

Each selecting device comprises a drum 36 mounted concentrically uponsaid shaft and connected thereto through the medium of apermanent'friction clutch 37, three cams 38 mounted rigidly upon saiddrum, and a se-' lector dial 39 which is free to rotate on said shaft,but may be locked by'loclr 40 relative to the'rigid frame of the unit atintervals of a twelfth of a revolution. Said selector dial carries astop 41 with which a correspending stop 42 on the drum is adapted toengage so that when the drum has rotated to a position determined by thesetting of the selector dial it is further.

The said lock 40 is rigidly mounted on a rotatable shaft 40a and has 2.lug 405 which when said shaft is rocked counter clockwise engages in anyone of a number of'notches at intervals in the edge of the dial 39 tolock said dial as stated. Said shaft is biased in this direction and ismovable manually in the other direction for releasing the dial.

Each cam has eight equally spaced radial projections 43 from itscircumferential periphery and the projections of the three cams are atequally staggered intervals. The three cams actuate respective contactfingers 44 which cooperate with respective fixed contacts 45 to make orbreak theth'ree circuits prevented from rotating m, y, 2, of the rotor(Z controlled by the particular selecting device, said fingers 44 beingclosed on said contacts 45 by the cam projections 43 sequentiallyincyclic order, each one being closed eight times per revolution of thedrum, so that if the three circuits are not otherwise interrupted, therotor will make twenty four steps or one complete revolution for eachcomplete revolution of the drum.

The same radial projections of the three cams also operate, through themedium of a train of links 46 the end 46a: of which is ex- 7 tendedlaterally as shown in Figure 8, so that it rides over all three drums, arecording drum 47 bearing type numerals on its periphery, thearrangement bein such that the position of said recording drum 47 alwayscorresponds to that of the particular rotor (5 con trolled by theparticular selecting device.

The four recording drums 47 appertaining to the whole transmission unitT are located side by side and thus correspond in position to the fourrotors (Z of the particular display set D. Alongside these fourrecording drums 47 are three time recording drums 48 actuated in a stepby step manner by means of an electromagnet 49 controlled by means of aclock 49a. These drums carry time type on their periphcries inoicativcof hours and minutes so that when a printing platen 50 is pressed downon to said drums 47 and 48 a record i printed on a record strip which ismoved along by any known means according as the platen 50 is presseddown, both of the numbers being signalled and the time at which theprint was taken.

Each transmission unit T also comprises an arm 51 rigidly mounted on theshaft 33 and carrying a bridging contact 52 adapted to bridge four fixedcontacts 53, 54, 55, 56 successively with a common fixed contact 57 asthe shaft 33 approaches and reaches the end of each revolution. Uponbridging of the first two of these contacts 53 and 54 respective gongs58 and 59 (Fig. 13) of different pitch in the vicinity of the displayset are sounded so that just before the shaft 33 com pletes eachrevolution a double note is signalled. Bridging of the third contact 55effects energization of an electric magnet 60 for pressing down theprinting platen 50 and printing a record of the number being signalledand the time the signal was started. The circuit for sounding the gong59 may be traced from line L1 the lower arm of the doublepole switch Sthrough conductors a. and 175 to the particular contact 57, through thebridging contact to the corresponding contact 53, through conductor 9,the winding of said gong 59 and through conductors g, m, a tothe upperarm of said switch S and line L2. The circuit for the gong 58 followsthe same path as the preceding circuit to the contact 57 and thenceextends through the bridging contact to the contact 54, throughconductor r the winding of said gong 58 and thence through conductors q,m, a to line L2 as in the preceding circuit. The circuit for energizingthe electromagnet 60 extends as in the preceding circuits to the contact57 and thence through the bridging contact to the contact 55 and throughconductor .9, said winding 60 and conductors a, c line L2. Bridging ofthe fourth contact 56 efi'ects stopping of the mo tor 66 as will be morefully described hereinafter.

Each transmission unit has associated therewith a transmission-startpush button 61, a signal-end push button 62, an electromagnetic switch63 and an electromagnetic lighting switch 64. The motor clapper switch63 when energized, closes to establish energizing circuit for the commonmotor 66 and an energizing circuit for the particular clutch 67appertaining to the transmission unit. Said former circuit extends fromline L1 through one arm of main switch S conductor a, the movablecontact of said switch 63, the fixed contact 65 of said switch 63,conductor 5, said motor 66, the other arm of said switch S back to lineL2. Said latter circuit extends from line L1 as previously traced tomovable contact of switch 63 and from there through fixed contacts 65a,conductor 0, said clutch 67 and conductors (Z and a back to line L2.

Said motor clapper switch 63 upon closure also establishes a maintainingcircuit for itself. Said circuit extending from line L1 contacts 65a aspreviously traced and from there through winding of switch 63,resistance r conductor 6 and upper arm of switch S to line L2.

The electromagnetic lighting switch 64 upon energization closes toestablish the cirtact of said switch 64, the fixed contact 64a,

conductor u, said lamps 69 in parallel conductors 7, 9,01, and e and theupper arm of switch S back to line L2. Said latter circuit extendsthrough the upper contact 64?) of said switch 64, conductor 2; throughsaid lamps 69a and back to line L2 as before.

The transmission-start push button 61 has upper contacts 70, 71 whichare normally bridged and lower contacts 72, 73 which are bridged upondepression of the button. When said lower contacts are bridged energizing circuit for said motor clapper switch is positivelyestablished, and a circuit for energizing the electromagnetic clutch isalso directly established. Said former circuit extends from line L1through lower arm of switch S said contacts 72 and 73, contact breakers79 whose purpose will hereinafter appear, conductor 0, the winding ofsaid switch 63, a resistance 7", conductor 6 and upper arm of switch Sto line L2. Said latter circuit extends as previously traced to circuitbreakers 79 and from there through said clutch 67 and conductors d, eand upper arm of switch S back to line L2. When the upper contacts 70and 71 ofsaid'transmission start.

push button 61 are closed said maintaining circuit for said motorclapper switch 63 is short circuited conditionally upon the contact 56being bridged with contact 57 as above described, said short circuitextending from the upper end of the winding of said switch 63 throughcontacts 65a, the movable contact of said switch 63, conductors a and h,said contacts 57 and 56, conduct r j and contacts 71 and 70 to the lowerend of said winding of said switch 63. v

The signal-end push button 62 has upper contacts 74, 7 5 which arenormally bridged and lower contacts 7 6, 77 which are bridged upondepression of the button. Said upper contacts 74, are connected in theenergizing circuit of the electro-magnetic lighting switch 64 whichcircuit extends from line L1 through lower arm of switch S, conductorconductors h and t, in parallel with contacts sion start push button61'is depressed the signal end push button is returned the full way toits normal position and its upper contacts 74, 75 are bridged; Thisinter-lock is illustrated in Figure 14. The contacts of 7 both pushbuttons 61 and '62 are mounted on is longitudinally movable and isbiased 80 a common fixed base B. The moving con tacts 61a and 62a areboth biased upwards by means of respective springs as shown. Extendingdownwardly from these moving contacts through the base B are respectiverods 61b and 62?). These rods at their lower ends carry heads 610and626', the head 610 coming more or less to a point at. its underside asshown. A plate C which to the left has holes as shown through which saidheads are adapted respectively to pass. When both push buttons are attheir up position the head 620 is'located in its hole in the plate C andthe head 610 is just above its hole.

WVhen the transmission start push button is depressed to its downposition the head 61c enters its hole so far as its upper or cylindricalportion and when sai d push button is released it returns to the upposition. lNhen now the push button '62 is depressed to the downposition the head 62?) leaves its hole and the plate C moves to the leftso that when said push button is released it does not return to the upposition but to an intermediate position where the head 620 is arrestedby the plate C. Said push bntton 62 will remain in this position untilthe push button 61 is again depressed when by virtueof the pointed endof its head entering its hole the plate is moved to the right, therebypermitting the push button 62 to return to its up position.

Said four circuit breakers 7 9 depend for their closure upon therespective locks 46 for the four selector dials 39 of the transmissionunit being in operation. Thus when shaft 40a (Figure 8) is rotated incounter clock wise direction a cam 4:00 on said shaft moves circuitbreaker 7 9 to open position. 60

WVhen it is required to actuate a given display set D, the selectordials 39 of the corre sponding transmission unit T are set according tothe numerals which the four rotors of the display set D are re uired toshow and the transmission-start pus button 61 of said transmission unitis depressed momentarily. Accordingly, the selector dials-39 beingprop-'- e'rly l'ocked and the circuit breakers 79 being thereforeclosed, circuits are established as previously described for energizingthe elect re-magnetic. clutch 67 and also the motor clapper switch 63.Said clapp r switch thereupon closes thereby establishing asaforedeserihed a circuit. for the common motor :66; a second circuit forthe elected magnetic Clutch 6'? so that thesihe will re main engagedwhen thetransniissionstart push button 61 is released and maintainingcircuit for itself.

The motor accordingly starts to run rotah ing the shaft 33 through themedium of said clutch 67. By the time the transmission start push button61 is released the Contact 56 will be disconnected from the bridgingContact 52 and therefore the maintaining circuit for the motor clapperswitch, soil responding drum 3-6 will be stopped by gagement of thestops 42 and' ll the friction clutch 37 slipping as the shaft 33 goescn.By the time the shaft 33 has almost completed one revolution therotorsfcl 'andrecording drums 47, 48 will all be set sta tionary. Firstthe two fixed contacts 53 and 54 will be sequentially bridged with thecommon fixed contact 57 and .i

the double note will be sounded on the gong-s 58 and 59 as previouslydescribed, and next the contact 55 will be so bridged whereupon theprinted record of the number signalled will be made as aforesaid;Finally the tilted contacts 56' will be bridged whereby, the

transmission start push button '61 being at normal, the winding of themotor clapper switch 63 will be short circuit'ed through'contacts and 71as previously described and: said clapper switch will open thereby deenergizing the electromagnetic clutch 67 and;

the motor 66 and bringing the shaft vto rest.

of the clapper switch 63- will close and, the

signal en'd push button 62 being at norm-ah.

energizing circuit for the winding oftlre lighting switch 64 will beestablished as viously described through contacts '74 and 75 agd thelamps 69 and 69a will be il-lilmi nate served that upon the clapperswitch 63 dos- At the same time the auxiliary contacts 78.

Iii)

Iii

When it is required to signal another 1111111 ber with said display setthe process is re=' peated, the selector di'alsi39 being reset and" thetransmission-start push button 61 being-' again momentarily depressed.It will be ing, the auxiliary contact 7 8 will open and break theenergizing circuit for the lighting switch 64 so that the illuminationwill go off immediately the transmission of the new signal is commenced.

If, although no newsignal isrequired, it is deemed that a signal hasbeen displayed long enough the signal end push button 62 isdepressedthereby breaking the said ener- 1 gizing circuit of the lighting switch64 and making, through contacts 55, 57 as previously described, theenergizing circuit for the winding 60 operating the printing platen 50..The illumination is accordingly switched off and 1 a printed record ismade of the signalled number and the time at which said illumination wasswitched off. Upon release of the signal-end push button 62 the printingplaten 50 is returned to normal but as said push button, does not returnto bridge its upper contacts but remains at an intermediate position theillumination is not again switched on.

When the transmission start push button 61 is again depressed fortransmitting. an-

other signal,the signal end push button 62 is returned to its upperposition as before stated so that the circuit for the lighting switch 64will be again completed when the shaft 33 has made its completerevolution and the new signal is set.

The individual connections by which the three circuits. w, y, z of eachrotor are sequentially established by the operation of the correspondingfingers 44 are shown only in the case of the top set of rollers inFigures 13,

and 13a in which the points 1A1M of Figure 13 are shown connected to thecorresponding points of Figure 13a. In'fact, the points 2A-4M of thesetwo figures are also simif larly connected. It will thus be seen whenany finger 44 is closed a corresponding circuit is established through arotor d said circuit extending from line L1, through lower arm of switchS, conductors a and la, through said finger 44 to (say) point 1A on lefthand side of'the figure, to point 1A on right hand side of figure,through the left hand circuit of the adjacent rotor d, conductors Z, m,n andc and upper arm of switch S back to o'line L2.

The numeral 82 designates pilot lamps at the central station'which aswill be clear from the drawings are'energized or not according aswhether the main switch S is or is not switched on. r

What we claim and desire to secure by Letters Patent is:

-1. In a remote control apparatus, a revoluble transmitter, a motor, aclutch adapted to transmit power from said motor for driving saidtransmitter, means for starting said motor,- preselectlng means forstopplng said transmitter-at a preselected rotary position, whereuponsaid clutch is adapted to slip, a

rotary controller adapted to be driven by said motor, atransmission-start1switch having positions a and b, an electromagneticmainswitch for said motor, means whereby movement of saidtransmission-start switch to position b efiects 'energization' of saidmain switch, means for establishing a maintaining circuit for said mainswitch upon closure thereof and 'means whereby upon arrival of saidcontroller at a given position said maintaining circuit is shortcircuited only if Said transmission-start? switch has returned toposition a. V

2. In a remote control apparatus, a plu-- rality of transmitters, acommon motor, respective friction drives for. transmitting power to saidtransmitters from said common motor, respective preselecting means forstopping the transmitters at any, desired position and means for causingthe motor to start in operation and continue in operation until acomplete cycle is finished whereby all of the transmitters aresimultaneously moved until stopped byv the preselecting means.

3. In a remote control apparatus a plurality of groups of transmitters,a common driving motor for all of said groups, group electro-magneticclutches through which said groups are adapted to be respectivelydriven, individual friction clutches in series .With said group clutchesthrough which the individual transmitters are adapted to be respectivelydriven, individual preselecting means for stopping the individualtransmitters atpreselected positions, starting means in connection witheach group upon operation of which the respective group clutch is.adapted to be closed and the motor simulta neously energized, and meansfor automatically stopping said motor and opening said group clutchafter said motor has run agiven amount suflicient toensure that themovement of all the transmitters of the'group has been completedwhatever the setting of the preselecting means.

4. In a remote control apparatus, a plurality of groups of transmitters,a common driving motor for all of said groups, group electromagneticclutches through which said groups are adapted to be respectivelydriven, individual frictional drives, through which the individualtransmitters are adapted to be respectively driven, individual means forpreselecting the amount through which said individual transmitters areto be respectively'moved and starting means in connection with eachgroup upon operation of which the respective group clutch is adaptedtobeclosed and the motor simultaneously energized. V o

In witness whereof we affix our signatures.

GORDON DOUGLASS. 1 STANLEY ROBERT l/VRIGHT.

